数控短电弧铣削加工工具电极损耗规律研究

发布时间：2018-03-27 16:57

本文选题：短电弧铣削　切入点：电极相对损耗　出处：《新疆大学》2017年硕士论文

【摘要】：短电弧加工技术采用正极性非接触脉冲放电方式来蚀除被加工工件,较机械加工优势比较明显,特别是对高硬度、高强度、高脆性、高红硬性的导电材料,加工效率比较理想。相对于电加工领域的电火花加工技术,短电弧转弊为利,创造性的把电火花中极力避免的电弧放电利用起来,进行工件的蚀除加工。其加工效率远高出电火花,并且在大型的水泥轧辊、磨煤辊、大型发动机机匣的加工中效果出色。本文主要对短电弧加工过程中的电极损耗规律进行了分析、总结、实验验证。实验采用新型的数控短电弧铣床对镍基高温合金进行加工。实验表明,电参数的差异,电极材料的差异,以及电极形状的差异对相对电极损耗的影响不同。实验中分别对短电弧铣削过程中常用的几种电极进行分析,实验发现采用相同的电参数和其他加工条件,石墨电极的相对损耗最小,紫铜随后,碳钢大于紫铜小于铝。相同的电极材料,在其他条件相同,电参数不同的情况下,电极的损耗不同。随着电压的增高电极的相对损耗呈减小的趋势;随着占空比的增大,电极的相对损耗质量呈增大趋势;随着频率的增大,电极的相对损耗质量呈增大趋势。研究中发现,采用合适的电极材料以及合理的加工电参数对减小电极损耗有明显的效果。在灰色理论的基础上,通过多目标下的工艺参数优化实验,对短电弧加工中的变量进行工艺参数的优化,通过进行正交实验得出实验数据,并设计出三项评价指标,分别为材料蚀除速度MRt,相对电极损耗EW.Rη,和表面粗糙度aR。通过对原始数据的量纲一化,求出每组实验三项指标的灰关联度。最终得出灰关联度最高的一组即为最优实验组合。在单因素实验中,分别对加工过程中的可变因素对电极相对损耗的影响规律进行验证,实验发现,理论分析与实验结果吻合。
[Abstract]:Short arc machining technique using non-contact pulse discharge to erosion workpiece machining more positive and more obvious advantages, especially for high hardness, high strength, high brittleness, high red rigid conductive material, the processing efficiency is ideal. Compared with EDM technology of EDM, short arc turn fraud for profit, according to arc discharge to avoid electric spark in use, the workpiece removal machining. The machining efficiency is far higher than the electric spark, and large roll in cement, coal grinding roller, the effect of the processing of large engine casing well. This paper focuses on the electrode loss law of short arc machining process in the analysis, summary, experimental verification. The experimental model of short arc NC milling machine for processing of nickel based alloy. The experimental results show that the difference of electrical parameters, the difference of the electrode material and electrode shape The difference of relative electrode wear is different. Respectively in the experiment of several commonly used electrode short arc milling process are analyzed, results also showed that the electrical parameters of the same and other processing conditions, the relative minimal loss of graphite electrode, copper copper aluminum steel is greater than the later, less than. The same electrode materials, under the same conditions. The electrical parameters under the condition of different electrode loss. With the increase of electrode voltage loss is relatively decreased; with the increase of duty ratio, the relative quality of electrode loss increases; with the increase of frequency, the relative loss showed an increasing trend. The study found that the quality of the electrode, using suitable electrode materials and the reasonable machining parameters have obvious effect to reduce the electrode loss. On the basis of the grey theory, the multi-objective optimization of the process parameters under the experiment, processing of short arc The optimization of variable parameters through orthogonal experiments, experimental data, and designed three indicators, respectively. The material removal rate of MRt, the relative electrode wear and surface roughness of EW.R and aR. by dimension of the original data a, calculate the grey correlation degree of each experiment three indicators the highest correlation. Finally a set of experiments is the optimum combination. In the single factor experiment, influence rule of variable factors in the process of relative electrode wear is verified, experiments, theoretical analysis and experimental results coincide.

【学位授予单位】：新疆大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG661;TG54

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